Reference operators¶
NGQL provides reference operators to represent a property in a WHERE or YIELD clause, or the output of the statement before the pipe operator in a composite query.
OpenCypher compatibility¶
Reference operators apply to native nGQL only.
Reference operator List¶
| Reference operator | Description |
|---|---|
$^ |
Refers to a source vertex property. For more information, see Property reference. |
$$ |
Refers to a destination vertex property. For more information, see Property reference. |
$- |
Refers to the output of the statement before the pipe operator in a composite query. For more information, see Pipe. |
Examples¶
```ngql
The following example returns the age of the source vertex and the destination vertex.¶
nebula> GO FROM "player100" OVER follow YIELD properties(\(^).age AS SrcAge, properties(\)$).age AS DestAge; +--------+---------+ | SrcAge | DestAge | +--------+---------+ | 42 | 36 | | 42 | 41 | +--------+---------+
The following example returns the name and team of the players that player100 follows.¶
nebula> GO FROM "player100" OVER follow \ YIELD dst(edge) AS id | \ GO FROM \(-.id OVER serve \ YIELD \(^.player.name AS Player, properties(\)\)).name AS Team; +-----------------+-----------+ | Player | Team | +-----------------+-----------+ | "Tony Parker" | "Spurs" | | "Tony Parker" | "Hornets" | | "Manu Ginobili" | "Spurs" | +-----------------+-----------+ ```